Process of making comb for shaving implements



March 11, 1941. v

J. BRUECKER PROCESS OF MAKING COMB FOR SHAVING IMPLEMENTS Filed Nov. 22, 1939 atented Mar. ll, 1941 UNITED STATES PATENT OFFICE I PROCESS OF MAKING COMB FOB. SHAVING IMPLEMENTS John Bruecker, Chicago, Ill.

Application November 22, 1939, Serial No. 305,713

,2 Claims.

This invention relates to the manufacture of a skin-engaging shearing member or comb adapted for use in a dry shaver and has more particular reference to the problem of making small shear- 5 ing teeth which will function satisfactorily in a shaver of this type.

An object of my invention is to provide an improved process of making a shearing member or comb of the character described having small shearing teeth which will have good edge-holding properties and will not irritate the skin and which will be sufliciently durable to maintain these characteristics in continued use.

Another object is to provide a process of mak- 15 lng small shearing teeth of the character de- 25 the body of the plate, flexing or bending the plate to a curvature approximating that which it occupies in cooperation with a movable cutting member, and grinding or lapping the inner side of the plate as well as the teeth while maintained in 0 said curvature.

Another object of my invention is to improve the manufacture of a shearing member of the character described with the view to reducing the cost thereof.

Referring to the drawing in which I have shown several embodiments;

Fig. 1 is an enlarged plan view of a shearing member or comb punched or blanked to shape in accordance with one'of the steps of my invention;

Fig. 2 is a further enlargement of a fragmen- 50 the lapping or grinding operation;

Fig. 7 is a fragmentary side elevation showing the thin member applied to a supporting frame; Fig. 8 is a cross-section through the shearing member and a movable cutter in cooperation therewith; and

Figs. 9 and 10 are enlarged fragmentary plan views showing modified forms of small teeth made in accordance with my invention.

The thin shearing member in which the small teeth are to be formed in accordance with my invention may be used in dry shavers having characteristics generally similar to my co-pendin application serial No. 178,221, filed December 6, 1937, for Shaving implement. The shearing member is preferably formed from thin resilient 10 steel sheet or plate stock which is properly tempered to give good edge-holding properties for the cutting edges. Also, in the preferred embodiment, this thin member is secured to a skeleton-like supporting frame having accurately finished arched ribs to which the thin member conforms. As taught in my prior application, the thin member and the supporting frame constitute a replaceable unit and the thin member may be united to the supporting frame by any of various means or methods.

The present invention deals primarily with the manufacture of a skin-engaging shearing member of the character described and more particularly with the incorporation in said member'of small tooth-like formations of a kind adapted not only for close shaving, but also for picking up or engaging beneath long or irregular hairs and for functioning to position them across the shearing edges so that they will be out off by co-action with a movable cutter. In Fig. 1 I have shown a thin shearing member ll of the character described which may be of a few thousandths in thickness, say approximately from .002" to .004" and which may be of any suitable or preferred shape consistent with the invention. In the initial process of manufacture this member is punched or perforated by one or more operations to provide hairreceiving openings. In the form here shown small teeth I2 are blanked to the general shape disclosed in my prior application and openings l3 providing cutting edges of a different shape are punched in the central area. The openings I4 at both sides of these areas are for the discharge of cut hair. The openings l3 and I4 are not essential so far as my present invention is concerned. However, the main shaving area covered by the openings l3 may embody small openings providing tooth-like cutting elements in keeping withmy present invention. This may be a series of rows of teeth such as II, or small tooth formations such as shown in the modified forms, Figs. 9 and 10, or any small tooth formations having the shape characteristics of the present invention.

After punching or blanking the teeth l2 these with respect to the flat plate i! This angular re-.

laticn is shown in Fig. 3, as corresponding with the angle of the end portions it, and in this particular case the bending is performed substan tlally along the base line of the teeth in a rectangular form indicated by IS. The thin member is then flexed approximately to the curvature which it is intended to keep in its final operative condition in cooperation with the movable cutter. This curvature is indicated in Fig. 4 and in the flexing of the thin member or plate to this position the projecting teeth are caused to bend back to an angular position preferably just short of their original position. This outward displacement of the teeth is caused by reason of stressing the metal between the teeth and the contiguous body portion of the thin plate by reason of flexing or bending the thin plate. This leaves the outer face of the teeth slightly inclined inwardly and likewise the inner edges i1 slight projecting at the inner surface of the plate. Following this the inner surface of the thin plate is lapped or ground while maintaining the plate in the curvature just described. This grinding operation is shown diagrammatically in Fig. 5 in which the abrasive tool i8 has a radius approximately that to which the thin plate is to occupy in its final operative condition. Roughing and finishing grinding operations may be used. This step in the process is covered in my Patent No. 2,182,067, granted December 5, 1939. In Fig. 6 is shown the tooth portion after the grinding operation, it being noted that the inner faces of the small teeth are flush with the inner surface of the thin plate ii. In this grinding or lapping operation the small teeth are accurately finished at their inner sides andthe' cutting edges I! are ground to a high degree of precision so that they will be maintained in the desired co-relation with the movable cutter.

Figs. '7 and 8 show the thin plate ll applied to. a skeleton supporting frame designated generally by lil having arched ribs 2! to which the thin plate is conformed and secured, as disclosed in my above mentioned application. Here also is shown a cutter blade 22 carried in a holder 23 mounted to oscillate about a center concentric with the inner surface of the thin plate ii. In actual operation in a dry shaver the cutter blade oscillates very rapidly and is urged by centrifugal forceor-spring pressure, or both, into intimate shearing engagement with the side of the thin member II and the cutting edges II. My present invention is not, however, confined to this type of cutter.

In Figs. 9 and 10 I have shown modified forms of small teeth, the manufacture of which is carried out similar to'the teeth I 2, as above described; In Fig. 9 the teeth 24 are V-shaped or crescent shaped and each tooth projects into an opening of similar shape. Here, each tooth 24 is bent inwardly substantially along the dotted line 25 corresponding with the operation shown in Fig. 2. In Fig. 10 the teeth 28 are quarterly spaced and project into a cross-shaped opening. These teeth are formed in a manner similar to the teeth 24. The tooth formations of Figs. 9 and 10 may be used eifectively in place of the small openings I3, or they may comprise the entire tooth structure in a dry shaver.

While I have shown a particular embodiment of m invention, it will be understood that I do not wish to be limited thereto since many modifications may be made, and I therefore contemplate by the appended claims to cover any such modifications as fall within the true spirit and scope of my invention.

I claim:

1. The process of forming small shearing teeth projecting from a thin resilient steel plate which is used as the skin-engaging shearing member of a shaving implement, including the steps of forming the plate to provide the profile shape of the teeth, bending the teeth to a set position toward the shearing edge side of the plate, flexing the plate to position the toothed portion in an arc and thereby causing the teeth to bend back to an angular position just short of their original position by inherent stress between the metal of the teethand the contiguous portion of the plate, and lapping the inner side of the plate together with the projecting inner face of the teeth by a lapping tool the face of which is of an arc approximately that of the cutting tool with which the shearing member is intended for use.

2. The process of making a skin-engaging shearing member for a shaving implement includlng the steps of perforating a thin resilient steel plate to provide a plurality of small projecting teeth, one side of which is for movement over the skin and the other is adapted to provide shearing edges, bending the teeth inwardly toward the shearing edge side to a set angular position with relation to the face of the plate, flexing the perforated portion of the plate to approximately the curvature it will occupy when in operative position in a shaving implement, said flexing step causing the teeth to bend outwardly to a lesser angular relation to the inner face of the member with certain of the shearing edges of the teeth projecting inwardly beyond said inner face, and grinding the interior surface of theperforated portion together with the inner face of the teeth by means of a grinding tool having a radius approximately that of the'curvature to which the perforated portion is flexed.

JOHN BRUECKER. 

